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    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <script>
    //    平均数

        let arr = [4, 6,88,333,12,77,92,0,13,666]
        let sum = 0
        for (let i = 0; i < arr.length; i++) {
            sum += arr[i]
        }
        console.log(sum);
        let Average = sum / arr.length
        console.log(Average);
    </script>
</body>
</html>